Materiały źródłowe

• #1 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR

  https://pmc.ncbi.nlm.nih.gov/articles/PMC7288848/

  Aortic insufficiency (AI) or regurgitation is caused by the malcoaptation of the aortic valve (AV) cusps due to intrinsic abnormalities of the valve itself, a dilatation or geometric distortion of the aortic root, or by some combination thereof. […] Recent close examination of such pathological processes has demonstrated a wide array of complex, active remodeling mechanisms affecting the valve and surrounding structures. […] New and ongoing research into the pathophysiology underlying these remodeling mechanisms has facilitated important discoveries pertaining to preventative, diagnostic, and mitigating strategies for patients with AI. […] This review will aim to describe various mechanisms involved in AI development, dissect some of the cross-talk among known and possible signaling pathways leading to valve remodeling, identify an association between these pathways and possible pharmacological approaches, and discuss surgical implications for management of these pathological processes.

• #1 Chronic aortic regurgitation: diagnosis and therapy in the modern era

  https://www.escardio.org/Journals/E-Journal-of-Cardiology-Practice/Volume-18/chronic-aortic-regurgitation-diagnosis-and-therapy-in-the-modern-era

  Aortic regurgitation (AR) is a complex and multifactorial valvular disease. […] Aortic regurgitation (AR, also termed aortic insufficiency) results in diastolic blood flow from the aorta back into the left ventricle (LV) and may be caused by a variety of acquired or congenital aetiologies preventing complete coaptation of the aortic valve (AV) leaflets (also called cusps). Primary (organic) AR is an intrinsic disease of the AV leaflets, whereas secondary (functional) AR results from distortion or dilation of the aortic root and/or ascending aorta leading to incomplete aortic leaflet coaptation. […] Some disease entities may cause AR by both mechanisms. For example, Marfans syndrome and bicuspid aortic valve (BAV) pathologies do affect the structure of the AV and may also cause dilatation of the aortic root and ascending aorta leading to a functionally regurgitant valve. Endocarditis may cause valve destruction by erosion of the leaflet edges or leaflet perforation.

• #1 Functional and pathomorphological anatomy of the aortic valve and root for aortic valve sparing surgery in tricuspid and bicuspid aortic valves – Jahanyar- Annals of Cardiothoracic Surgery

  https://www.annalscts.com/article/view/17021/html

  The aortic valve (AV) is a three-dimensional structure, with leaflets that are suspended within the functional aortic annulus (FAA). These structures (AV and FAA) are therefore intrinsically connected and disease of just one component can independently lead to AV dysfunction. Hence, AV dysfunction can occur in the setting of entirely normal valve leaflets. However, as these structures are functionally inter-connected, disease of one component can lead to abnormalities of the other over time. Thus, AV dysfunction is often multifactorial. […] Loss of integrity of any of these components leads to AV dysfunction, regurgitation or even stenosis. Moreover, based on the principles of the mechanism of mitral regurgitation set forth by Alain Carpentier, Gebrine El Khoury has developed the functional classification for aortic regurgitation (AR) during the late 90s and early into the new millennium.

• #1 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR

  https://pmc.ncbi.nlm.nih.gov/articles/PMC7288848/

  On a cellular level, the AV is comprised of valvular interstitial cells (VICs) and valvular endothelial cells (VECs), both of which are seeded within intricate, interactive networks of extracellular matrices. […] Considering the dynamic microenvironment present within the AV, the hemodynamic changes demonstrated in patients with AI can contribute strongly to the progression of the disease, even in the setting of an asymptomatic patient. […] Ultimately, these hemodynamic changes to the local environment can then lead to further remodeling in the AV through an interplay between molecular, cellular, and structural signaling pathways. […] At the molecular level, the AV contains various protein families that regulate and maintain valve structure and function, primarily through interactions with the extracellular matrix (ECM).

• #1 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR

  https://pmc.ncbi.nlm.nih.gov/articles/PMC7288848/

  The ECM is an important regulator of cell and tissue function and may be defined as the diverse collection of proteins and sugars that surrounds cells in all solid tissues. […] The organized valvular ECM makes up the cusps of the valve and contains three overlapping layers, each with distinct properties: the ventricularis, the spongiosa, and the fibrosa. […] Given the highly interconnected network of proteins and pathways involved in ECM maintenance that have been implicated in AI development, it is safe to suggest that the ECM changes are at the center of the network from which valve remodeling occurs. […] Cardiac remodeling resulting in AI can manifest itself in various ways, such as prolapse, degeneration, and calcification, which can result in changes in the hemodynamic properties of the valve. […] The rise of proteomics and knockout studies on individual proteins in mice over recent years has demonstrated that numerous different proteins can contribute to AV remodeling and AI when inactivated.

• #1 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR

  https://pmc.ncbi.nlm.nih.gov/articles/PMC7288848/

  Hyaluronan, a glycosaminoglycan (GAG), constitutes 60% of the total GAG content in the heart and carries out various functions including cell interactions and linking proteins with aggrecan, making it an important component of the valvular ECM. […] Another family of proteins implicated in AV remodeling and regulation are matricellular proteins. […] In the regulation of the AV structure, the transforming growth factor beta (TGF-) superfamily is one of the largest molecular components. […] Given TGF-s important role in ECM organization, any valvular remodeling will likely be associated with altered TGF- expression, thereby directly impacting the molecular structure of the AV. […] As aforementioned, a major protein with significant impact on the ECM is TGF-. […] Given the wide array of genomic and proteomic pathways involved in AV dysregulation, it becomes clear that many more genes and proteins likely contribute to this process as well.

• #1 Aortic Regurgitation: Background, Pathophysiology, Etiology

  https://emedicine.medscape.com/article/150490-overview

  The pathophysiology of AR depends on whether the AR is acute or chronic. In acute AR, the LV does not have time to dilate in response to the volume load, whereas in chronic AR, the LV may undergo a series of adaptive (and maladaptive) changes. […] Acute AR of significant severity leads to increased blood volume in the LV during diastole. The LV does not have sufficient time to dilate in response to the sudden increase in volume. As a result, LV end-diastolic pressure increases rapidly, causing an increase in pulmonary venous pressure and altering coronary flow dynamics. […] Chronic AR causes gradual left ventricular volume overload that leads to a series of compensatory changes, including LV enlargement and eccentric hypertrophy. LV dilation occurs through the addition of sarcomeres in series (resulting in longer myocardial fibers), as well as through the rearrangement of myocardial fibers.

• #1 Aortic regurgitation pathophysiology – wikidoc

  https://www.wikidoc.org/index.php/Aortic_regurgitation_pathophysiology

  In acute aortic insufficiency, there is a sudden decrease in stroke volume and subsequent increase in left ventricular end diastolic volume thereby causing decrease cardiac output with resultant reflex tachycardia. The sharply rising high left ventricular end diastolic pressure and reflex tachycardia causes profound hypotension and cardiogenic shock. […] In chronic aortic insufficiency, initially the left ventricle remains complaint, thereby compensates for increased left ventricular end diastolic volume by progressive left ventricular dilatation and left ventricular hypertrophy, which maintains normal ratio of wall thickness to the cavity radius, thereby maintaining normal wall stress. Overtime, when the left ventricular hypertrophy fails to keep up with chronic volume overload, end systolic wall stress rises and at this point the left ventricle fails and results in left ventricle decompensation causing reduction in the left ventricular wall compliance with resultant congestive heart failure.

• #1 Acute aortic regurgitation in adults – UpToDate

  https://www.uptodate.com/contents/acute-aortic-regurgitation-in-adults

  The acute onset of severe aortic regurgitation (AR, also called aortic insufficiency) is usually a medical emergency due to the inability of the left ventricle to quickly adapt to the abrupt increase in end-diastolic volume caused by the regurgitant flow. If not surgically corrected, acute severe AR commonly results in cardiogenic shock. […] Aortic dissection can result in AR by four mechanisms: dilation of the sinuses with incomplete coaptation of the leaflets at the center of the valve; involvement of a valve commissure resulting in inadequate leaflet support; direct extension of the dissection into the base of a leaflet, resulting in a flail valve leaflet; and prolapse of the dissection flap across the aortic valve into the left ventricular outflow tract in diastole impeding leaflet closure. Patients with a bicuspid aortic valve are at higher risk of aortic dissection.

• #1 6.5: Aortic Regurgitation – Medicine LibreTexts

  https://med.libretexts.org/Bookshelves/Medicine/Textbook_of_Cardiology/06%3A_Valvular_Disease/6.05%3A_Aortic_Regurgitation

  Aortic root dilatation, annular dilation and congenital bicuspid valve are, in developed countries, the most common causes of severe chronic aortic valve regurgitation. […] The slow process of chronic aortic regurgitation allows adaptation of the ventricle to the increased preload and afterload. […] The left ventricle compensates to the regurgitant flow, the increased volume and pressure by enlargement. […] In contrast to the compensatory mechanism in mitral valve regurgitation, a modest concentric left ventricular hypertrophy accompanies the eccentric hypertrophy, with a normal mass-to-volume ratio. […] In a chronic state, progressive left ventricle dilatation leads to pre- and afterload mismatch.

• #1 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #1 Aortic Regurgitation: Background, Pathophysiology, Etiology

  https://emedicine.medscape.com/article/150490-overview

  Eventually, the LV reaches its maximal diameter and diastolic pressure begins to rise, resulting in symptoms (dyspnea) that may worsen during exercise. Increasing LV end-diastolic pressure may also lower coronary perfusion gradients, causing subendocardial and myocardial ischemia, necrosis, and apoptosis.

• #1 Aortic regurgitation – Wikipedia

  https://en.wikipedia.org/wiki/Aortic_regurgitation

  Aortic regurgitation causes both volume overload (elevated preload) and pressure overload (elevated afterload) of the heart. […] The volume overload, due to elevated pulse pressure and the systemic effects of neuroendocrine hormones causes left ventricular hypertrophy (LVH). There is both concentric hypertrophy and eccentric hypertrophy in AI. The concentric hypertrophy is due to the increased left ventricular pressure overload associated with AI, while the eccentric hypertrophy is due to volume overload caused by the regurgitant fraction. […] Physiologically, in individuals with a normally functioning aortic valve, the valve is only open when the pressure in the left ventricle is higher than the pressure in the aorta. This allows the blood to be ejected from the left ventricle into the aorta during ventricular systole. The amount of blood that is ejected by the heart is known as the stroke volume. Under normal conditions, 50% of the blood in a filled left ventricle is ejected into the aorta to be used by the body. After ventricular systole, the pressure in the left ventricle decreases as it relaxes and begins to fill up with blood from the left atrium. This relaxation of the left ventricle (early ventricular diastole) causes a fall in its pressure. When the pressure in the left ventricle falls below the pressure in the aorta, the aortic valve will close, preventing blood in the aorta from going back into the left ventricle.

• #1 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #1 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #1 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #1 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #1 Aortic valve regurgitation – Symptoms and causes – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/aortic-valve-regurgitation/symptoms-causes/syc-20353129

  In aortic valve regurgitation, the aortic valve doesn’t close properly. This causes blood to flow backward from the body’s main artery, called the aorta, into the lower left heart chamber, called the left ventricle. […] Aortic valve regurgitation also called aortic regurgitation is a type of heart valve disease. The valve between the lower left heart chamber and the body’s main artery doesn’t close tightly. As a result, some of the blood pumped out of the heart’s main pumping chamber, called the left ventricle, leaks backward. […] In aortic valve regurgitation, the valve doesn’t close properly. This causes blood to leak back into the lower left heart chamber, called the left ventricle. As a result, the chamber holds more blood. This could cause it to get larger and thicken. […] Any condition that damages the aortic valve can cause aortic valve regurgitation. Causes may include:

• #1 Incidence and Pathology of Aortic Regurgitation | ICR Journal

  https://www.icrjournal.com/articles/incidence-and-pathology-aortic-regurgitation?language_content_entity=en

  Aortic regurgitation (AR) can arise from degenerative, congenital, inflammatory and infectious aetiologies, manifesting as primary AR with intrinsic leaflet disease, secondary AR due to aortopathy or annular dilatation, or a combination. […] The aetiology of AR may be diverse, encompassing degenerative (degeneration of aortic root and/or aortic leaflet), congenital, inflammatory and infectious factors. The AR mechanism can be primary with aortic valve leaflet abnormality, secondary with preserved aortic leaflets such as aortic root or annular dilatation, or a combination. […] Aortic valve leaflet degeneration is the dominant cause of primary AR. Primary AR consists of calcific degenerative leaflet disease, commonly associated with AS. […] Other causes of primary AR feature intrinsic leaflet disorders such as leaflet perforation, prolapse, or restriction.

• #1 Incidence and Pathology of Aortic Regurgitation | ICR Journal

  https://www.icrjournal.com/articles/incidence-and-pathology-aortic-regurgitation?language_content_entity=en

  In secondary AR, the aortic valve leaflets appear structurally normal. Aortic root pathology with dilatation can create secondary AR through aortic valve leaflet malcoaptation, retraction and prolapse. […] The bicuspid aortic valve phenotype is the most common congenital heart defect, and associated with AR in 20-70% of cases. […] Primary AR can develop due to abnormal shear stress leading to degenerative leaflet thickening, restriction, or prolapse. […] Connective tissue disorders such as Marfan, Loeys-Dietz and vascular Ehlers-Danlos syndromes commonly result in secondary AR due to aortopathy. […] The main cause of acute secondary AR is aortic dissection, which may be iatrogenic or due to the above-mentioned aortopathies. […] In acute AR, the sudden onset of severe diastolic regurgitation results in a rapid increase in LV end diastolic volume and pressure, which may spiral towards pulmonary congestion and cardiogenic shock. In chronic AR, the left ventricle has the time to adapt to the volume overload and the LV end diastolic pressure volume relationship flattens, which postpones the occurrence of symptoms. Remodelling includes LV dilatation, eccentric hypertrophy and increased stroke volume to compensate for the regurgitation volume. However, over time the incessant volume overload will overrule the ventricular compensatory remodelling capacity. Eventually, this cascade will progress to LV dilatation, myocardial fibrosis and systolic failure with depressed LVEF.

• #1 Aortic valve regurgitation – Symptoms and causes – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/aortic-valve-regurgitation/symptoms-causes/syc-20353129

  Other rare conditions can cause the aorta to get bigger and damage the aortic valve. These include a connective tissue disease called Marfan syndrome. Some immune system conditions, such as lupus, also can lead to aortic valve regurgitation. […] Tear or injury of the body’s main artery. The body’s main artery is the aorta. A traumatic chest injury may damage the aorta and cause aortic regurgitation. So might a tear in the inner layer of the aorta, called an aortic dissection.

• #1 CV Physiology | Valvular Insufficiency (Regurgitation)

  https://cvphysiology.com/heart-disease/hd005

  Aortic regurgitation occurs when the aortic valve cannot close completely and blood flows back from the aorta (Ao) into the left ventricle after ejection into the aorta is complete. […] Because the ventricle is being filled from two sources (aorta and LA), this leads to much greater LV filling; therefore, LV end-diastolic volume increases, which increases LV end-diastolic pressure (20 mmHg in this example). […] Therefore, a defining characteristic of aortic regurgitation is an increase in aortic pulse pressure (systolic minus diastolic pressure). […] The elevation in LV end-diastolic pressure causes blood to back up into the left atrium and pulmonary veins, which increases left atrial pressure and pulmonary capillary wedge pressure, and can cause pulmonary congestion and edema. […] The backward flow of blood into the ventricular chamber during diastole results in a diastolic murmur.

• #1 CV Physiology | Aortic Regurgitation

  https://cvphysiology.com/heart-disease/hd009d

  effects of aortic regurgitation on ventricular pressure-volume loopsThe following describes changes that occur in the left ventricular pressure-volume loop when there is aortic regurgitation. In aortic valve regurgitation (red loop in figure), the aortic valve does not close completely at the end of systolic ejection. As the ventricle relaxes during diastole, blood flows from the aorta back into the ventricle, so the ventricle immediately begins to fill from the aorta (before filling from the left atrium). Therefore, there is no true phase of isovolumetric relaxation (no vertical line between aortic valve closure and mitral valve opening) because as the ventricle relaxes, even before the mitral valve opens, blood is entering the ventricle from the aorta, thereby increasing ventricular volume.

• #1 CV Physiology | Aortic Regurgitation

  https://cvphysiology.com/heart-disease/hd009d

  Once the mitral valve opens, filling occurs from the left atrium; however, blood continues to flow from the aorta into the ventricle throughout diastole because aortic pressure is higher than ventricular pressure during diastole. This augments ventricular filling so that end-diastolic volume is increased as shown in the pressure-volume loop. Ventricular end-diastolic volume is also increased because in chronic aortic regurgitation the ventricle anatomically dilates (remodels), which increases ventricular compliance. […] When the ventricle begins to contract and develop pressure, blood is still entering the ventricle from the aorta because aortic pressure is higher than ventricular pressure; therefore, there is no true isovolumetric contraction because volume continues to increase. Once the ventricular pressure exceeds the aortic diastolic pressure, the ventricle ejects blood into the aorta. The increased end-diastolic volume (increased preload) activates the Frank-Starling mechanism to increase the force of contraction, ventricular peak (systolic) pressure, and stroke volume (as shown by the increased width of the pressure-volume loop).

• #1 Aortic Regurgitation | Thoracic Key

  https://thoracickey.com/aortic-regurgitation-4/

  The majority of causes of aortic regurgitation produce chronic volume overload with slow indolent left ventricular dilation and a prolonged asymptomatic phase. […] In chronic aortic regurgitation excessive preload and excessive afterload may overcome the ability of the left ventricle to compensate via hypertrophy and recruitment of preload reserve, leading to left ventricular systolic dysfunction. This may occur in the absence of symptoms. […] The left ventricle responds to the volume load of chronic AR with a series of compensatory mechanisms, including an increase in end-diastolic volume, an increase in chamber compliance that accommodates the increased volume without a rise in filling pressures, and a combination of eccentric and concentric hypertrophy. […] The central hemodynamic feature of chronic AR is combined volume and pressure overload of the left ventricle.

• #1 Aortic Regurgitation | Thoracic Key

  https://thoracickey.com/aortic-regurgitation-4/

  As the disease progresses, recruitment of preload reserve and compensatory hypertrophy permit the left ventricle to maintain normal ejection performance despite the elevated afterload. […] LV systolic dysfunction (defined as an EF below normal at rest) is initially a reversible phenomenon related predominantly to afterload excess, and full recovery of LV size and function is possible with aortic valve replacement (AVR). […] With time, during which the left ventricle develops progressive chamber enlargement and a more spherical geometry, depressed myocardial contractility predominates over excessive loading as the cause of progressive dysfunction. […] A number of studies have identified LV systolic function and end-systolic size as the most important determinants of survival and postoperative recovery of LV function in patients undergoing valve replacement for chronic AR.

• #1 Aortic regurgitation pathophysiology – wikidoc

  https://www.wikidoc.org/index.php/Aortic_regurgitation_pathophysiology

  Aortic insufficiency causes both volume overload (elevated preload) and pressure overload (elevated afterload due to the increased stroke volume) of the heart. Regurgitation of blood into the left ventricle causes volume overload and a rise in preload. The pressure overload causes left ventricular hypertrophy (LVH). There is both concentric hypertrophy and eccentric hypertrophy in AI. […] The increasing regurgitant volume causes the stroke volume to fall. In order to compensate for a fraction of the blood going backwards, the heart compensates by ejecting a larger total volume of blood forward. The ejection fraction is preserved and perhaps even increased to compensate for the regurgitant fraction. […] While the left ventricular dilation is associated with the increased cardiac output according to the Frank-Starling mechanism, at a certain point of left ventricular dilation, the left ventricle begins to fail as left ventricular contractility falls. Once wall thickening fails to keep up with the hemodynamic load, end systolic wall stress rises and at this point the left ventricle fails. The dramatic enlargement of the heart that is seen with aortic insufficiency is called cor bovinum. […] It has been said that 'aortic regurgitation begets aortic regurgitation’. The high oscillatory shear associated with aortic regurgitation may lead to further dilation of the aorta, which in turn may lead to further worsening of aortic regurgitation.

• #1 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR – PubMed

  https://pubmed.ncbi.nlm.nih.gov/32529168/

  The aim of this review is to describe some of the putative mechanisms implicated in the development of AI, dissect some of the cross-talk among known and possible signaling pathways leading to valve remodeling, identify association between these pathways and pharmacological approaches, and discuss the implications for surgical and percutaneous approaches to AV repair in replacement in the TAVR era.

• #1 Echocardiographic assessment of aortic regurgitation: a narrative review | Echo Research & Practice | Full Text

  https://echo.biomedcentral.com/articles/10.1186/s44156-023-00036-7

  Aortic regurgitation (AR) is the third most frequently encountered valve lesion and may be caused by abnormalities of the valve cusps or the aorta. […] Echocardiography is central to the diagnosis and quantification of AR severity, in addition to delineating the aetiology and mechanism of valve insufficiency. […] AR may present and/or develop acutely or gradually and is caused by malcoaptation or malapposition of the AV cusps. […] This may be a result of abnormalities of the AV cusps and/or their supporting structures, including the AV annulus, the aortic root and the ascending aorta. […] Degenerative AV disease is more frequently encountered in the form of focal calcific deposits or diffuse fibrous thickening causing abnormal coaptation, although, rarely, myxomatous degeneration of the aortic cusps may also account for AR secondary to cusp thickening and/or prolapse.

• #1 Echocardiographic assessment of aortic regurgitation: a narrative review | Echo Research & Practice | Full Text

  https://echo.biomedcentral.com/articles/10.1186/s44156-023-00036-7

  The functional classification is an invaluable tool that helps clinicians systematically evaluate the valve behaviour and may influence the type of intervention chosen for the valve. […] The VC represents the smallest flow diameter of the regurgitant jet going through the AV, and provides a surrogate for the effective regurgitant orifice area (EROA) and an indicator of the AR severity. […] An EROA0.30cm2, regurgitant volume60mls and regurgitant fraction50% all indicate severe AR. […] In summary, a quantitative assessment of AR should be routinely performed for those patients with more than mild AR. […] Given its significant prognostic value, echocardiographic assessment of the LV is of paramount importance in the evaluation and management of patients with aortic regurgitation not only before but also after they have AV surgery.

• #1 Aortic Regurgitation

  https://www.healio.com/cardiology/learn-the-heart/cardiology-review/topic-reviews/aortic-regurgitation

  This results in increased systolic pressures, reduced diastolic pressures and widened pulse pressure. […] Increased stroke volume leads to a number of unusual peripheral physical examination findings. […] The low diastolic aortic pressures can significantly affect coronary perfusion pressures, as coronary flow occurs during diastole. […] Afterload (peripheral resistance) is an important factor in the degree of aortic regurgitation. […] All other factors being equal, increased peripheral resistance will be associated with increased regurgitation. […] Thus, afterload reduction has become the mainstay of pharmacotherapy in aortic regurgitation.

• #1 Aortic Valve Regurgitation | Cedars-Sinai

  https://www.cedars-sinai.org/health-library/diseases-and-conditions/a/aortic-valve-regurgitation.html

  In severe aortic regurgitation, surgery is commonly advised. The timing of surgery is important to discuss with your healthcare provider and surgeon. In some cases, severe aortic regurgitation may be treated with medicine. Medicine may also be used in the short-term before valve replacement surgery. Or it may be used ongoing if you are not able to have valve replacement surgery. […] Acute, severe aortic valve regurgitation needs surgery right away. You may need medicines for a short time to stimulate your heart or to dilate or constrict your blood vessels. In some cases, an infection of the heart valves can cause acute valve regurgitation. This may only need to be treated with antibiotics.

• #1 New minimally invasive treatment option for aortic regurgitation | MUSC Health | Charleston SC

  https://muschealth.org/health-professionals/progressnotes/2022/summer/aortic-regurgitation-treatment

  Blood flow through the heart is directed through four different valves, each with leaflets, or flaps, that act as one-way doors into the next chamber. But in aortic regurgitation, the aortic valve fails to close completely, and blood leaks backwards through it. […] Patients in South Carolina with severe aortic regurgitation previously had only one treatment option: open heart surgery. But with new transcatheter heart valve technology, a new aortic valve can be placed inside their diseased one by an already established, minimally invasive technique known as transcatheter aortic valve replacement (TAVR). […] This method proved successful for treating aortic stenosis which is when the valve narrows and restricts blood flow but it was not used to treat aortic regurgitation until now. […] With the device, physicians can place a healthy valve inside the leaky one by clipping it onto the natural valves original leaflets without using any sutures.

• #1 New minimally invasive treatment option for aortic regurgitation | MUSC Health | Charleston SC

  https://muschealth.org/health-professionals/progressnotes/2022/summer/aortic-regurgitation-treatment

  This new device makes TAVR possible for a greater number of patients. […] The device aligns with the patients natural anatomy, he said. This allows for better and more efficient blood flow to the hearts arteries. […] Another drawback to traditional TAVR techniques is coronary re-access, according to Amoroso, but the new valve allows for more successful valve access after placement, which is important for any future procedures. […] I think the procedure offers a treatment opportunity for a whole group of patients whom weve only been able to treat with open heart surgery in the past, he said. This valve offers an alternative for treating patients with aortic regurgitation with a minimally invasive technique that allows patients to recover more quickly.

• #2 Aortic Regurgitation: Background, Pathophysiology, Etiology

  https://emedicine.medscape.com/article/150490-overview

  Aortic regurgitation (AR) is the diastolic flow of blood from the aorta into the left ventricle (LV). Regurgitation is due to incompetence of the aortic valve or any disturbance of the valvular apparatus (eg, leaflets, annulus of the aorta) resulting in the diastolic flow of blood into the left ventricular chamber. […] Incompetent closure of the aortic valve can result from intrinsic disease of the leaflets, cusp, diseases of the aorta, or trauma. Diastolic reflux through the aortic valve can lead to left ventricular volume overload. An increase in systolic stroke volume and low diastolic aortic pressure produces an increased pulse pressure. The clinical signs of AR are caused by the forward and backward flow of blood across the aortic valve, leading to increased stroke volume. […] The severity of AR is dependent on the diastolic regurgitant valve area, the diastolic pressure gradient between the aorta and LV, and the duration of diastole.

• #2 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR – PubMed

  https://pubmed.ncbi.nlm.nih.gov/32529168/

  Aortic insufficiency (AI) or regurgitation is caused by the malcoaptation of the aortic valve (AV) cusps due to intrinsic abnormalities of the valve itself, a dilatation or geometric distortion of the aortic root, or by some combination thereof. […] In recent years, there has been an increase in the number of studies suggesting that AI is an active disease process caused by a combination of factors including but not limited to alteration of specific molecular pathways, genetic predisposition, and changes in the mechanotransductive properties of the AV apparatus. […] However, these techniques necessitate frequent reappraisal of the biological and mechanobiological mechanisms underlying AV regurgitation to better understand the risk factors for AI development and recurrence following surgical intervention as well as expand our limited knowledge on patient selection for such procedures.

• #2 Incidence and Pathology of Aortic Regurgitation | ICR Journal

  https://www.icrjournal.com/articles/incidence-and-pathology-aortic-regurgitation?language_content_entity=en

  Aortic regurgitation (AR) can arise from degenerative, congenital, inflammatory and infectious aetiologies, manifesting as primary AR with intrinsic leaflet disease, secondary AR due to aortopathy or annular dilatation, or a combination. […] The aetiology of AR may be diverse, encompassing degenerative (degeneration of aortic root and/or aortic leaflet), congenital, inflammatory and infectious factors. The AR mechanism can be primary with aortic valve leaflet abnormality, secondary with preserved aortic leaflets such as aortic root or annular dilatation, or a combination. […] Aortic valve leaflet degeneration is the dominant cause of primary AR. Primary AR consists of calcific degenerative leaflet disease, commonly associated with AS. […] Other causes of primary AR feature intrinsic leaflet disorders such as leaflet perforation, prolapse, or restriction.

• #2 Functional and pathomorphological anatomy of the aortic valve and root for aortic valve sparing surgery in tricuspid and bicuspid aortic valves – Jahanyar- Annals of Cardiothoracic Surgery

  https://www.annalscts.com/article/view/17021/html

  The El Khoury classification thus explains all the different types of AR and illustrates the loss of the geometric relationship between AV-structures. Hence, in analogy to Carpentiers classification: AR type I corresponds to dilation of the FAA; type II corresponds to an excess of leaflet motion (prolapse); and type III to restricted leaflet motion. […] The different mechanisms of AR can be isolated, but they more frequently occur simultaneously in patients with AR especially in cases of long-standing severe AR, large aneurysmal disease or congenital AV disease. […] The goal of AV-sparing surgery and repair is to restore the geometric relationship between the different components of the AV and root, and also to stabilize the repair, which improves long-term durability. Therefore, the surgical toolbox should entail techniques to repair or remodel any component of the AV/root complex; valve-sparing root replacement techniques hereby represent a major tool in the available surgical armamentarium.

• #2 Aortic Valve Regurgitation: Pathophysiology and Implications for Surgical Intervention in the Era of TAVR

  https://pmc.ncbi.nlm.nih.gov/articles/PMC7288848/

  The ECM is an important regulator of cell and tissue function and may be defined as the diverse collection of proteins and sugars that surrounds cells in all solid tissues. […] The organized valvular ECM makes up the cusps of the valve and contains three overlapping layers, each with distinct properties: the ventricularis, the spongiosa, and the fibrosa. […] Given the highly interconnected network of proteins and pathways involved in ECM maintenance that have been implicated in AI development, it is safe to suggest that the ECM changes are at the center of the network from which valve remodeling occurs. […] Cardiac remodeling resulting in AI can manifest itself in various ways, such as prolapse, degeneration, and calcification, which can result in changes in the hemodynamic properties of the valve. […] The rise of proteomics and knockout studies on individual proteins in mice over recent years has demonstrated that numerous different proteins can contribute to AV remodeling and AI when inactivated.

• #2 Aortic Regurgitation – Cardiovascular Disorders – Merck Manual Professional Edition

  https://www.merckmanuals.com/professional/cardiovascular-disorders/valvular-disorders/aortic-regurgitation

  Aortic regurgitation (AR) is incompetency of the aortic valve causing backflow from the aorta into the left ventricle during diastole. […] Aortic regurgitation may be acute (very uncommonly) or chronic. […] In aortic regurgitation, volume overload of the left ventricle (LV) occurs because the LV receives blood regurgitated from the aorta during diastole in addition to blood from the left atrium. […] In acute aortic regurgitation, the LV does not have time to dilate to accommodate the increased volume, which then causes a rapid increase in left ventricular pressure and subsequently pulmonary edema and decreased cardiac output. […] In chronic aortic regurgitation, LV hypertrophy and dilation can gradually occur, so normal left ventricular pressures and cardiac output are maintained. But decompensation eventually develops, ultimately causing arrhythmias, LV impairment, and heart failure (HF).

• #2 Acute aortic regurgitation in adults – UpToDate

  https://www.uptodate.com/contents/acute-aortic-regurgitation-in-adults

  The acute onset of severe aortic regurgitation (AR, also called aortic insufficiency) is usually a medical emergency due to the inability of the left ventricle to quickly adapt to the abrupt increase in end-diastolic volume caused by the regurgitant flow. If not surgically corrected, acute severe AR commonly results in cardiogenic shock. […] Aortic dissection can result in AR by four mechanisms: dilation of the sinuses with incomplete coaptation of the leaflets at the center of the valve; involvement of a valve commissure resulting in inadequate leaflet support; direct extension of the dissection into the base of a leaflet, resulting in a flail valve leaflet; and prolapse of the dissection flap across the aortic valve into the left ventricular outflow tract in diastole impeding leaflet closure. Patients with a bicuspid aortic valve are at higher risk of aortic dissection.

• #2 Chronic aortic regurgitation: diagnosis and therapy in the modern era

  https://www.escardio.org/Journals/E-Journal-of-Cardiology-Practice/Volume-18/chronic-aortic-regurgitation-diagnosis-and-therapy-in-the-modern-era

  In fixed subaortic stenosis, which is usually classified as a congenital lesion, the incessant high-pressure jet may damage the aortic leaflets. Therefore, some degree of AR is frequently incurred in a progressive manner dependent on the severity of obstruction. […] Chronic AR generally evolves slowly and imposes a combined volume (manifested by LV enlargement) and pressure overload (indicated by increased end-systolic pressure) on the LV. This hybrid haemodynamic overload results in remodelling of the LV to normalise wall stress and maintain systolic function and is characterised by eccentric hypertrophy and LV dilatation to accommodate for the regurgitant volume. […] The onset of symptoms (spontaneous or on exercise testing) represents a key development and denotes the strongest indication for intervention.

• #2 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #2 Aortic regurgitation pathophysiology – wikidoc

  https://www.wikidoc.org/index.php/Aortic_regurgitation_pathophysiology

  Aortic insufficiency causes both volume overload (elevated preload) and pressure overload (elevated afterload due to the increased stroke volume) of the heart. Regurgitation of blood into the left ventricle causes volume overload and a rise in preload. The pressure overload causes left ventricular hypertrophy (LVH). There is both concentric hypertrophy and eccentric hypertrophy in AI. […] The increasing regurgitant volume causes the stroke volume to fall. In order to compensate for a fraction of the blood going backwards, the heart compensates by ejecting a larger total volume of blood forward. The ejection fraction is preserved and perhaps even increased to compensate for the regurgitant fraction. […] While the left ventricular dilation is associated with the increased cardiac output according to the Frank-Starling mechanism, at a certain point of left ventricular dilation, the left ventricle begins to fail as left ventricular contractility falls. Once wall thickening fails to keep up with the hemodynamic load, end systolic wall stress rises and at this point the left ventricle fails. The dramatic enlargement of the heart that is seen with aortic insufficiency is called cor bovinum. […] It has been said that 'aortic regurgitation begets aortic regurgitation’. The high oscillatory shear associated with aortic regurgitation may lead to further dilation of the aorta, which in turn may lead to further worsening of aortic regurgitation.

• #2 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #2 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #2 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #2 Aortic Regurgitation – Aortic Valve Disease – Valvular Heart Disease – Cardiovascular Diseases – Diseases – McMaster Textbook of Internal Medicine

  https://empendium.com/mcmtextbook/chapter/B31.II.2.8.2.

  Aortic regurgitation (AR) is a reversal of blood flow from the aorta into the left ventricle (LV) due to incomplete closure of the aortic valve leaflets. […] Primary regurgitation is caused by damage to or a congenital abnormality of the leaflets, with subsequent dilation of the left ventricular outflow tract, aortic annulus, and ascending aorta. […] Secondary regurgitation is caused by dilation of the aortic annulus and the ascending aorta (secondarily causing malcoaptation of the aortic valve leaflets) in the absence of significant aortic valve leaflet pathology. […] 1) Primary: Congenital (bicuspid aortic valve, quadricuspid aortic valve, valve damage in subaortic stenosis); degenerative (calcifications, fibrosis); infective endocarditis (active or healed); rheumatic; drug-induced (fenfluramine, phentermine) damage of the leaflets.

• #2 Incidence and Pathology of Aortic Regurgitation | ICR Journal

  https://www.icrjournal.com/articles/incidence-and-pathology-aortic-regurgitation?language_content_entity=en

  In secondary AR, the aortic valve leaflets appear structurally normal. Aortic root pathology with dilatation can create secondary AR through aortic valve leaflet malcoaptation, retraction and prolapse. […] The bicuspid aortic valve phenotype is the most common congenital heart defect, and associated with AR in 20-70% of cases. […] Primary AR can develop due to abnormal shear stress leading to degenerative leaflet thickening, restriction, or prolapse. […] Connective tissue disorders such as Marfan, Loeys-Dietz and vascular Ehlers-Danlos syndromes commonly result in secondary AR due to aortopathy. […] The main cause of acute secondary AR is aortic dissection, which may be iatrogenic or due to the above-mentioned aortopathies. […] In acute AR, the sudden onset of severe diastolic regurgitation results in a rapid increase in LV end diastolic volume and pressure, which may spiral towards pulmonary congestion and cardiogenic shock. In chronic AR, the left ventricle has the time to adapt to the volume overload and the LV end diastolic pressure volume relationship flattens, which postpones the occurrence of symptoms. Remodelling includes LV dilatation, eccentric hypertrophy and increased stroke volume to compensate for the regurgitation volume. However, over time the incessant volume overload will overrule the ventricular compensatory remodelling capacity. Eventually, this cascade will progress to LV dilatation, myocardial fibrosis and systolic failure with depressed LVEF.

• #2 Aortic Regurgitation – Aortic Valve Disease – Valvular Heart Disease – Cardiovascular Diseases – Diseases – McMaster Textbook of Internal Medicine

  https://empendium.com/mcmtextbook/chapter/B31.II.2.8.2.

  2) Secondary: Idiopathic aortic dilation; hypertensive aortic dilation; systemic connective tissue diseases (rheumatic disease, rheumatoid arthritis, aortic stenosis); dilation or dissection of the ascending aorta (hypertension, Marfan or Marfan-like syndrome, atherosclerosis, inflammation, trauma, myxomatous degeneration); aortopathy associated with bicuspid aortic valve; syphilitic aortic disease.

• #2 Aortic Regurgitation: Symptoms, Causes & Treatment

  https://my.clevelandclinic.org/health/diseases/24396-aortic-regurgitation

  Over time, this can cause the muscular walls of your left ventricle to thicken and dilate (left ventricular hypertrophy). This makes your heart less efficient. Other complications may include heart failure and arrhythmia. […] Acute aortic regurgitation can cause pulmonary edema (fluid in your lungs) and lower your cardiac output.

• #2 CV Physiology | Aortic Regurgitation

  https://cvphysiology.com/heart-disease/hd009d

  Once the mitral valve opens, filling occurs from the left atrium; however, blood continues to flow from the aorta into the ventricle throughout diastole because aortic pressure is higher than ventricular pressure during diastole. This augments ventricular filling so that end-diastolic volume is increased as shown in the pressure-volume loop. Ventricular end-diastolic volume is also increased because in chronic aortic regurgitation the ventricle anatomically dilates (remodels), which increases ventricular compliance. […] When the ventricle begins to contract and develop pressure, blood is still entering the ventricle from the aorta because aortic pressure is higher than ventricular pressure; therefore, there is no true isovolumetric contraction because volume continues to increase. Once the ventricular pressure exceeds the aortic diastolic pressure, the ventricle ejects blood into the aorta. The increased end-diastolic volume (increased preload) activates the Frank-Starling mechanism to increase the force of contraction, ventricular peak (systolic) pressure, and stroke volume (as shown by the increased width of the pressure-volume loop).

• #2 6.5: Aortic Regurgitation – Medicine LibreTexts

  https://med.libretexts.org/Bookshelves/Medicine/Textbook_of_Cardiology/06%3A_Valvular_Disease/6.05%3A_Aortic_Regurgitation

  Aortic root dilatation, annular dilation and congenital bicuspid valve are, in developed countries, the most common causes of severe chronic aortic valve regurgitation. […] The slow process of chronic aortic regurgitation allows adaptation of the ventricle to the increased preload and afterload. […] The left ventricle compensates to the regurgitant flow, the increased volume and pressure by enlargement. […] In contrast to the compensatory mechanism in mitral valve regurgitation, a modest concentric left ventricular hypertrophy accompanies the eccentric hypertrophy, with a normal mass-to-volume ratio. […] In a chronic state, progressive left ventricle dilatation leads to pre- and afterload mismatch.

• #3 Echocardiographic assessment of aortic regurgitation: a practical guideline from the British Society of Echocardiography | Echo Research & Practice | Full Text

  https://echo.biomedcentral.com/articles/10.1186/s44156-024-00067-8

  Aortic regurgitation (AR) is the result of aortic cusp abnormality, aortic root (AoR) dilatation, or a combination of the two. […] It is useful to classify the mechanism of valve insufficiency into one of three subtypes: Type I AR is characterised by normal cusp motion within the context of aortic dilatation or cusp perforation; Type II describes excessive motion such as cusp prolapse; and Type III is the consequence of cusp restriction. […] The functional classification is a useful tool that helps clinicians systematically evaluate the valve behaviour and may influence the type of intervention chosen for the valve. However when reporting, it may be necessary to describe the mechanism rather than just quote the functional classification type. This would ensure findings are effectively communicated, relatable and transferable across echocardiographer, referrer and receiver (i.e. normal cusp motion in the setting of a dilated aorta).

• #3 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

• #3 Aortic Regurgitation – Aortic Valve Disease – Valvular Heart Disease – Cardiovascular Diseases – Diseases – McMaster Textbook of Internal Medicine

  https://empendium.com/mcmtextbook/chapter/B31.II.2.8.2.

  Aortic regurgitation (AR) is a reversal of blood flow from the aorta into the left ventricle (LV) due to incomplete closure of the aortic valve leaflets. […] Primary regurgitation is caused by damage to or a congenital abnormality of the leaflets, with subsequent dilation of the left ventricular outflow tract, aortic annulus, and ascending aorta. […] Secondary regurgitation is caused by dilation of the aortic annulus and the ascending aorta (secondarily causing malcoaptation of the aortic valve leaflets) in the absence of significant aortic valve leaflet pathology. […] 1) Primary: Congenital (bicuspid aortic valve, quadricuspid aortic valve, valve damage in subaortic stenosis); degenerative (calcifications, fibrosis); infective endocarditis (active or healed); rheumatic; drug-induced (fenfluramine, phentermine) damage of the leaflets.

• #4 Pathophysiology of aortic regurgitation and management | PPT

  https://www.slideshare.net/slideshow/pathophysiology-of-aortic-regurgitation-and-management-129052303/129052303

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